Homework #2 1) What are the definitions of polarization, wavelength and wavenumber? Polarization has to do with the relative direction of the particle motion and the wave motion. There are two general types of polarization, transverse and longitudina
Due Feb. 15
Question 9 a) Hearing around corners is possible because of diffraction. One way to understand diffraction is by using Huygen's principle. b) All other things being equal (for example assume they play with equal s
1) On a clear (cloudless) night the air temperature is often lower near the ground than it is higher up. Draw a sketch and explain why it is that on such nights you can usually hear sounds from far away. Note also that the earth
Question 1 Draw graphs of the following. a. A square wave of period T= 10 ms and amplitude A=1 V
b. A sawtooth wave of period T=2 ms and amplitude A=2 V
c. A triangular wave of period T=5 ms amplitude A=3 V
Calculate the fr
Homework #2 1) What are the definitions of polarization, wavelength and wavenumber? 2) What is the relationship between pressure and force? What is the relationship between mass-density and mass? What are the units for each of these four quantities?
Homework #4 1) On a clear (cloudless) night the air temperature is often lower near the ground than it is higher up. Draw a sketch and explain why it is that on such nights you can usually hear sounds from far away. Note also that the earth tends to
Homework #1 Question 1 Draw graphs of the following. a. A square wave of period T= 10 ms and amplitude A=1 V b. A sawtooth wave of period T=2 ms and amplitude A=2 V c. A triangular wave of period T=5 ms amplitude A=3 V Calculate the frequencies of th
Thoughts on the metaphysics of Science "How can science claim to be truth?"
Truth-Finding is a process that rests on epistemology your beliefs about what you can and can't know. Any process of finding truth rests on a belief concerning what
Some more details on Sound
There are two main ingredients to wave motion inertia and restoring force. These are the two ingredients that go into the mathematical description of sound waves. There are three ideas that come into play, and each idea ha
Physics of Sound
1. Fourier analysis and synthesis of waves. 2. Fourier Analysis of tones. 3. Tone quality.
Mathematically, any sound can be analyzed in terms of (taken apart seen as the linear superposition of) pure c
Impedance A very useful concept for understanding the flow of energy is called the impedance. Energy flow, or the rate at which energy is being used, is called power. If you push on a moving object with a force F and it moves with velocity v then the
Friday 7 Name:_ Speech synthesis and analysis What parallels exist (what is the analogy) between the vocal tract and a music synthesizer? Both can make a wide variety of sounds. Both have a power source. Both start with an oscillator (vocal chords) o
The ear and hearing.
Name_ Section_ The critical band. The ear performs frequency analysis on sound. The place theory of hearing associates a specific location on the cochlea for each frequency. The response of the cochlea is a maximum at
Friday 6 Intervals, overtones, and axis. The overtone series for one-dimensional standing waves on a medium of length L and wave speed v is: nv fn = 2L Here n is an integer: 1,2,3,4,. Each of these overtones corresponds to a "mode of vibration" of th
Name:_ Impedance Matching Friday 5
We have been saying that if the impedance is matched between two media, then there will be no reflection of waves as energy passes from one medium to another. If a wave pulse passes from medium number 1 with impeda
Physics of Sound 2008
Question 1 A wave is observed to have a period of 0.5 seconds and a wavelength of 2 meters. What is the wave propagation speed? Frequency is the inverse of period, so the frequency is 1/(0.5s)= 2 Hz
For sound waves, the relation between frequency f and wavelength of a harmonic wave is determined by the sound speed in a medium v: v= f . Wave speed equals frequency times wavelength. This relation always holds if you are
Friday #3 Wave Propagation Wave propagation on ropes and strings depends on the two ingredients of inertia and linear restoring force. For a rope or string we define its inertia in terms of how much mass there is for a given length. We will use the s
Friday 2 Name:_ Activity: The simple harmonic oscillator
The spring constant is the slope of the force vs position line. What is the spring constant in the experiment?
The slope is 0.2 N divided by 0.1 m. This is 2N/m.
What is the period of the os
Name:_ Activity: Period and frequency. Periodic motion repeats itself in time after and interval called the "period" [For this we use the symbol T ]. Frequency is another way to express the same thing by indicating how frequently (how many times) the